How to Grow Milkweed Plants to Help Monarch Butterflies
Monarch Butterfly Populations are Crashing -- Here's What You Can Do
When I was young, I set out on a plan to learn every butterfly species that occurred in my part of the country (upper Midwest USA). One of the first of these was the beautiful and regal monarch butterfly, Danaus plexippus. It is one of the best-known insects in the world. The monarch is often the first butterfly people learn to identify, and it occurs throughout North America as well as many other parts of the world. But the monarch is in critical danger. Shocking new data indicate that this iconic insect is experiencing a population crash. Less that twenty years ago, the number of monarch butterflies hibernating in the pine-covered mountains of northern Mexico was estimated at one billion individuals; this year, the estimate is only 35 million. This means you and I will see far fewer of these majestic insects, if we see them at all. The monarch is on its way to becoming a very rare sight across North America.
But all is not lost -- there are things you and I can do to help pull this species back from the brink.
Why Are Monarch Butterflies Becoming Rare?
To understand the most likely reason for the decline in monarch butterfly numbers, you need to know a little about the life-cycle of the insect. Like all butterflies, the monarch goes through four stages of development. This is called "complete metamorphosis," and in this case it means the insect begins life as an egg, which hatches into a caterpillar. The tiny caterpillar does nothing but eat, storing energy for the adult phase. When the caterpillar is full grown, it enters the third phase, or pupa (also commonly known as a "chrysalis"). During this time the caterpillar is being rearranged into the winged adult, a process that truly boggles the mind. But when it's complete, the butterfly breaks out of the pupa, unfurls its wings, and flies off to find a mate. If the purpose of the caterpillar phase was to accumulate fat and energy, the purpose of the adult is to find a mate, lay eggs, and keep the cycle going. It's a beautiful process that is still being studied by scientists.
The Milkweed Connection
Since the caterpillar is the "eating" stage of the monarch and all other butterflies, it's critically important that there's enough food to go around. Monarch caterpillars are very picky -- they only eat one kind of plant, the milkweed (family Asclepias). There are several species of milkweed that occur in the monarch's range, and up until recently the plant was abundant in open places, along roadsides, and on the edges of fields. It was easy to find the caterpillars feeding on the leaves of milkweed plants across the entire country not so long ago, in ditches and field borders throughout the Midwest and East. Now, this magnificent animal is on the brink of extinction.
Here's Where You Can Get Milkweed Seeds
It's simple to start bringing the monarchs back by growing milkweed. The good people at monarch watch.org have created a campaign to bring back monarchs by helping us plant milkweed. Their website provides a list of milkweed seed suppliers throughout the country, as well as excellent tips for finding and spreading wild milkweed on your own. This is a great example of a motivated group of people devoting time and energy to great cause, and they deserve our support.
If you have ever watched a big orange butterfly drifting on the breeze and sensed the endless beauty and power of nature, then you must realize what's at stake.
Watch as a Monarch Butterfly Hatches
Kill Milkweed, Kill Monarchs
Since the monarch needs a healthy crop of milkweed to feed on, the butterfly's survival is directly connected to the survival of milkweed plants across the country. But in the last two decades, the number of milkweed plants has plummeted. Part of this phenomenon may be related to climate change, but researchers have identified a more destructive force. It's thought that modern agricultural practices, specifically the use of genetically altered soybean and other crops, has caused wild milkweed to nearly vanish from the places it was once abundant.
Monarch Caterpillars on Milkweed
Monarch Caterpillars Rely on Milkweed
Most caterpillars have very specific food plant needs. They have evolved along with the plant, and will often die before they eat a different leaf. Monarchs are very strictly tied to milkweed species, and the female will basically never lay her eggs on any other kind of plant. The caterpillars may be protected by the toxic white sap of the milkweed (the "milk"), and their striped coloring suggests a warning to birds and other predators that they taste bad, and may even by poisonous.
Genetic Engineering and the Decline of the Monarch
The connection between genetically modified crops and the decline of the monarch butterfly is direct and backed by research. Genetically modified crops lead to the destruction of all other plants in the vicinity. In fact, that's the whole idea behind this kind of agriculture. These plants are genetically altered to be impervious to the strong herbicides that farmers spray around them. The herbicides -- plant poison -- kill everything but the modified soybeans, corn, and so on. This means healthier crops, lower prices, and more abundant food. It's not entirely a bad thing, since you and I benefit directly from this arrangement. It's modern science and technology in action.
But the monarch butterfly, obviously, does not benefit. Since the milkweed it depends on is killed by the herbicides along with all the other "weeds" in the vicinity, there are far fewer caterpillars that grow up to become adults. Let this pattern repeat for several years, and the number of butterflies you and I see dwindles rapidly.
New Hope for Monarchs -- And It Starts With a Flower
Things do indeed look bleak for the survival of our most spectacular butterfly. With milkweed being destroyed by more aggressive herbicide use, and monarch population numbers down to a fraction of their normal level, it's not unimaginable that the monarch will become a very rare, if not extinct, species.
But you and I can make a difference. Planting milkweed in our backyards and parkways will provide monarchs with the food plants they need. If enough people join this initiative, the plant can become common again (apart from the agricultural areas where it may never return).
Milkweed grows fast, is tolerant of most climates, and has beautiful flowers that attract a multitude of butterfly species, including the monarch. It needs very little care. There is hardly a garden or yard that wouldn't look better with a few milkweed plants in it.
Take a Quick Poll
Would you consider planting milkweed to help feed the monarch?
Happiness is a butterfly, which when pursued, is always just beyond your grasp, but which, if you will sit down quietly, may alight upon you.— Nathaniel Hawthorne